Noninvasive Evaluation of the Vascular System

Noninvasive Evaluation of the Vascular System


The evaluation of the patient with arterial disease begins with a thorough history and physical examination and uses noninvasive vascular studies as an adjunct to confirm a clinical diagnosis and further define the level and extent of vascular pathology. Vascular testing may be indicated for patients with suspected arterial disease based upon symptoms (eg, intermittent claudication), physical examination findings (eg, signs of tissue ischemia), or in patients with risk factors for atherosclerosis (eg, smoking, diabetes mellitus) or other arterial pathology (eg, trauma, peripheral embolism) .

A variety of noninvasive examinations are available to assess the presence and severity of arterial disease. Physiologic tests include segmental limb pressures and the calculation of pressure index values (eg, ankle-brachial index, wrist-brachial index), exercise testing, segmental volume plethysmography, transcutaneous oxygen measurements, and photoplethysmography.

Ultrasound is the mainstay for preliminary investigative and noninvasive vascular imaging, with each mode (eg, B-mode, duplex) providing specific information that is useful depending on the vascular disorder. Other studies frequently used to image the vasculature include computed tomography (CT) and magnetic resonance (MR) angiography. CT and MR are important adjunctive or alternative methods for vascular assessment; however, the cost and the time necessary for these studies may limit their use for routine testing [2]. Catheter-based arteriography remains the definitive, but invasive, vascular imaging modality and is often selected if concomitant intervention is being considered. The role of imaging in specific vascular disorders is discussed in individual disease-specific organ reviews.

INDICATIONS FOR TESTING

The need for noninvasive vascular testing to supplement the history and physical examination depends upon the clinical scenario and urgency of the patient's condition. An exhaustive battery of tests is not required in all patients to evaluate their vascular status. In general, only tests that confirm the presence of arterial disease or provide information that will alter the course of treatment should be performed.

Patients can be asymptomatic or have classic symptoms of peripheral artery disease (PAD) such as claudication, or more atypical symptoms. Symptoms vary depending upon the vascular bed affected, the nature and severity of the disease, and the presence and effectiveness of collateral circulation. The clinical presentations of various vascular disorders are discussed in separate topic reviews. (See "Clinical features and diagnosis of lower extremity peripheral artery disease" and "Overview of thoracic outlet syndromes" and "Clinical manifestations and diagnosis of the Raynaud phenomenon" and "Clinical features and diagnosis of abdominal aortic aneurysm".)


Author:

Erica Mitchell, MD, FACS

Section Editors:

John F Eidt, MD

Joseph L Mills, Sr, MD

Deputy Editor:

Kathryn A Collins, MD, PhD, FACS